Crocs - Are there too many?

A “salty” at Hartley’s Crocodile Adventures

The Australian public, if not the whole world, has a soft spot for Crocodylus porosus, due largely to the amazing work of the late Steve Irwin, alias the Crocodile Hunter, as well as the timeless blockbuster movie, Crocodile Dundee.

But in the opinion of many, perhaps including myself, the conservation of "salties" (as the estuarine crocodiles are called here in northern Queensland) has been taken too far. They are exceedingly dangerous animals and their numbers have increased dramatically from around 5000 in the 70's (when they wereplaced on the proteced list) to around 150,000 in 2008.

There are now large numbers in close proximity to human habitation and you never know where they will turn up - on popular beaches or even in the middle of cities. Deaths from salties, though still uncommon, are apparently becoming more frequent and causing great concern amongst those who have to live alongside them.

While estuarine crocodiles are an extremely fascinating and ancient species, claims that they play an important role in maintaining the balance of wetland ecosystems are probably over-stated. I suppose it depends what balance you want - was the balance in 1974 any “less healthy” than the balance now?

Whichever way you look at it, the impact of crocs on the local environment is completely overshadowed by the impact of invasive species, in particular the cane toad, for which environmentalists have no answer.
As adult crocs are at the top of the food chain in their habitat, their impact on the environment could well be seen as mainly negative. Their prey includes birds, wallabies, turtles, snakes, lizards, frogs and fish. It seems that freshwater crocodiles, and to a lesser extent salties, also eat cane toads and may be killed by them, so it's possible the toads will put a clamp on croc populations without the intervention of man. Or maybe just the opposite will occur, because some predators of crocodile eggs and baby crocs are themselves being poisoned by cane toads!

Although baby crocs are eaten by just about everything else bigger than themselves (including adult male crocs), a reduction in their numbers would probably have little effect on the food chain because the niche they occupy would presumably be filled by other small fry that would become more numerous following the decline in the population of adult crocs. (Not forgetting the role of the toads!)

Of course, it is imperative to ensure that reasonable sized populations of the species are preserved in all their major habitats. The Queensland Government has a quite broad-minded conservation plan which aims to do just that. Amongst other things it allows for the removal of crocs from urban areas and for their commercial exploitation (mainly through crocodile farming).

But by tagging them with the “vulnerable species” label, it is inevitable that the interests of the salties will continue to be given priority. Which means they will continue to thrive and multiply. Unfortunately we humans are doing the same, and more of us are venturing into traditional croc territory.

The crocs seem to be winning - paradoxically with a lot of help from ourselves. They are no loger under threat and the conservation program needs to ease up.

Surely we now have too many of these ferocious killers and it's high time we started culling them again, at least in areas frequented by humans. For more information (especially important for overseas travellers to the outback) see Australian Saltwater Crocodiles).

Comments:
1. It’s a pity the public hasn’t been educated to enjoy and understand living things at the lower end of the food chain - such as plankton - which matter very much to the planet and whose existence is threatened by climate change and other global factors.
2. For those of us living in a suburban environment there are many much more obnoxious creatures than crocodiles, among them Inian mynas, termites, domestic dogs and cats and their owners!
3. This article perhaps belies my general outlook on conservation, outlined here.